The state of an electron in a hydrogenic atom is given by the un-normalised wavefunction

Φ = \(\left\{Y_{10}(\theta, \phi) +\frac{1}{\sqrt2}Y_{11}(\theta, \phi)\right\}R(r)\)

where Yim (θ, ϕ) are spherical harmonics and R(r) is the radial function. The probability that a measurement of Lz will give an eigenvalue of h is

This question was previously asked in
CSIR-UGC (NET) Chemical Science: Held on (18 Sept 2022)
View all CSIR NET Papers >
  1. 1/2
  2. \(\frac{1}{\sqrt2}\)
  3. 1/3
  4. \(\frac{1}{\sqrt3}\)

Answer (Detailed Solution Below)

Option 3 : 1/3
Free
Seating Arrangement
3.4 K Users
10 Questions 20 Marks 15 Mins

Detailed Solution

Download Solution PDF

Concept:

The hydrogenic wavefunctions are solutions to the Schrödinger equation for the hydrogen atom (or hydrogen-like ions) and are characterized by three quantum numbers: n (the principal quantum number), l (the angular momentum quantum number), and ml (the magnetic quantum number).

The specific form of the wavefunction depends on these quantum numbers, and there are mathematical expressions to calculate the radial and angular parts of the wavefunction for each allowed set of quantum numbers.

Given:

Lz = ℏ

Explanation:

According to Variation Theorem, eigen value for Lz is

Lz = mℏ

∴ m =1

⇒ Calculating Probability for m=1 ie. Y11

\(P(m=1)={P(Y_{11}) \over Total Proliability}\)

\(P(m=1)= {(1/\sqrt{2})^2 \over (1/\sqrt{2})^2 + 1^2}\)

\(P(m=1)={1\over3}\)

Conclusion:

The probability for Lthat will give eigen value of h is \({1\over 3}\).

Latest CSIR NET Updates

Last updated on Jun 5, 2025

-> The NTA has released the CSIR NET 2025 Notification for the June session.

-> The CSIR NET Application Form 2025 can be submitted online by 23rd June 2025

-> The CSIR UGC NET is conducted in five subjects -Chemical Sciences, Earth Sciences, Life Sciences, Mathematical Sciences, and Physical Sciences. 

-> Postgraduates in the relevant streams can apply for this exam.

-> Candidates must download and practice questions from the CSIR NET Previous year papers. Attempting the CSIR NET mock tests are also very helpful in preparation.

More Basic Principles of Quantum Mechanics Questions

Get Free Access Now
Hot Links: teen patti casino teen patti club teen patti master apk best teen patti bodhi teen patti rules